Due to high performance implemented in mobile devices such as smartphones and tablet PCs, an AP speed may be increased, while a resolution of an image to be displayed increases. Due to an increase in the power usage as a dual or quad core central processing unit (CPU) is used, a thin film-type inductor mainly used for a DC-DC converter and a noise filter requires low dc resistance to be implemented, with high inductance.
In addition, the miniaturization and thinning of various electronic devices are accelerating with the development of manufacturing technology. Accordingly, a thin film-type inductor used in such electronic devices is also required to be miniaturized and thinned.
To manufacture a small, high capacity thin film power inductor, a coil requires a high aspect ratio, and a body requires a highly charged magnetic sheet. However, even if a high-aspect-ratio coil and a highly charged body are implemented, loss characteristics need to be further improved in order to implement characteristics in a very small size. In detail, in the case of a via pad connecting an upper coil to a lower coil, although the influence on the entire DC resistance (Rdc) is not greatly affected, the characteristic deterioration may be produced through an electrode in the vicinity of the via pad. In addition, since there are limitations in reducing a size of a via, even if a thin film-type power inductor is miniaturized, a ratio of chip charging loss by the via pad tends to be higher as a thin film-type power inductor is miniaturized.